Capillary Flow Technology with Multi-Dimensional Gas Chromatography for Trace Analysis of Oxygenated Compounds in Complex Hydrocarbon Matrices

Abstract

By employing multi-dimension gas chromatography with capillary flow technology in combination with highly selective capillary columns and a pressurized liquid injection system, light oxygenated compounds such as methanol, ethanol, n-propanol, 2-propanol, and n-butanol in the presence of either light hydrocarbon, heavy hydrocarbon, or aromatic matrices can be measured accurately with minimal possibility of a false positive. Using this technique, a detection limit of at least 0.20 ppm (w/w) with a linear correlation coefficient greater than 0.9993 over a range from 0.5 ppm to 600 ppm (w/w) and a relative standard deviation of greater than 2.7% are achieved for the solutes tested. The technique can also be effective for the measurement of other classes of oxygenated compounds such as ethers, aldehydes, and ketones. Another added benefit for the implementation of capillary flow technology is the capability to conduct column back-flushing, where heavier, undesired solutes in a sample can be back-flushed from the chromatographic system to improve system cleanliness and sample throughput.

Applications of planar microfluidic devices and gas chromatography for complex problem solving

“…The analysis of target compounds in complex matrices remains a challenge for 1D GC, despite the variety of column stationary phases available. Multidimensional GC is a logical and cost‐effective extension of GC carried out on a single column for target compound analysis . GC‐GC, also known as heart‐cutting, either by a multiport valve or by flow modulation using a Deans’ switch, is a relatively simple, efficient way for implementing multidimensional GC in target analyses.…”

Multidimensional gas chromatography with capillary flow technology and LTM‐GC

“…In a conventional 2-D GC method, only the effluents of interest, typically coeluting pairs from the first dimension, are transferred to the second dimension. While this technique has been well practiced with packed and capillary column technologies [5, 6, 8 -14], recent developments in hardware such as capillary flow technology and LTM-GC make it practical and reliable for capillary GC column applications especially for in-field/quality control lab environments [21,22]. With conventional 2-D GC, two independent retention datasets can be generated, one for each dimension.…”

“…By manipulating the pressure and the switch valve on/off time, critical pairs from the first dimension can be effectively and reliably transferred to the second dimension for further separation [23 -25]. The principle of operation of capillary flow technology as a Deans switch device has been described in detail earlier by Quimby et al [22] and others [21]. Leak free connection through the use of metal ferrules, low void volume, high degree of inertness, high temperature of operation (up to 4008C), no moving parts, and the non-contact switching of capillary flow technology makes practicing conventional 2-D GC straightforward and highly reliable.…”

Multidimensional Gas Chromatographic Analysis of Low-Temperature Oxidized Jet Fuels: Formation of Alkyldihydrofuranones

“…12,13 Until recently, fuel oxidation was normally assessed via bulk physical or chemical property tests. Heart-cutting gas chromatographic techniques were first applied to the separation of low molecular weight oxygenated fuel additives by McCurry and Quimby 14 and then by Luong et al 15 and Sciarrone et al 16 some years later. Compounds arising from oxidation reactions, however, are generally of higher molecular weight, less volatile, and substantially more difficult to isolate from the fuel matrix via chromatography or other techniques.…”

“…Until recently, fuel oxidation was normally assessed via bulk physical or chemical property tests. Heart-cutting gas chromatographic techniques were first applied to the separation of low molecular weight oxygenated fuel additives by McCurry and Quimby and then by Luong et al and Sciarrone et al . some years later.…”